Question

The mean number of hours of study time per week for a sample of 524 high-school students is 27. If the margin of error for the population mean with a 98% confidence interval is 1.7, construct a 98% confidence interval for the mean number of hours of study time per week for all high-school students.

Lower endpoint?

upper endpoint?

Answer #1

Solution :

Given that,

Point estimate = sample mean = = 27

Margin of error = E = 1.7

At 98% confidence interval estimate of the population mean is,

- E < < + E

27 - 1.7 < < 27 + 1.7

25.3 < < 28.7

**Lower endpoint = 25.3**

**Upper endpoint = 28.7**

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